How do I know what values to use for rate and burst when I configure a policer?
A. These parameters control the operation of the token bucket: • Rate—Defines how many tokens are removed at each interval. This effectively sets the policing rate. All traffic below the rate is considered in-profile. • Interval—Defines how often tokens are removed from the bucket. The interval is fixed at 0.00025 seconds, so tokens are removed from the bucket 4,000 times per second. The interval cannot be changed. • Burst—Defines the maximum number of tokens that the bucket can hold at any one time. Burst should be no less than the rate times the interval in order to sustain the specified traffic rate. Another consideration is that the maximum-size packet must fit into the bucket. Use this equation in order to determine the burst parameter: Burst = (rate bps * 0.00025 sec/interval) or (maximum packet size bits) [whichever is greater] For example, if you want to calculate the minimum burst value needed to sustain a rate of 1 Mbps on an Ethernet network, the rate is defined as 1 Mbps an
